Compliant hydrodynamic gas bearings are used in high performance applications requiring tolerance of high temperature and speed, for example, gas turbine engines. Such bearings exhibit superior operational and durability characteristics as compared to bearings which require liquid lubrication and liquid cooling systems.
One problem experienced in known hydrodynamic gas bearings is that the foil must be sufficiently compliant to conform to the supported member uniformly under all conditions, yet be fully supported so as to exhibit significant load capacity accompanied by an ability to control orbital motion. Orbital excursion of a shaft is due to the fact that a high-speed shaft tends to orbit about the geometric center of its bearing. The amplitude of the orbital motion is maximized at certain critical speeds and is especially critical in the case of small journal bearings. Proper control or elimination of high-speed instability by a multipoint suspension permits the bearing of the instant invention to operate to the burst speed of the rotating assembly.